Antidetonation combustion chamber for internal-combustion engines



A. MOORE April 9, 1929.

ANTIDETONATION COMBUSTION CHAMBER FOR INTERNAL COMBUSTION ENGINES Original Filed Oct. 11, 1926 r INVENTOR Ww h ATTORNEY titans PATENT *DFFMZE.

ARLINGTON MOORE, OF NEW YORK, N. Y., ASSIGNOR, BY MESNE ASSIGNMENTS, TO MAXMOOR CORPORATION, OF NEW YORK, N '25., A CORPORATION OF DELAVJ'ABE.

ANTIDETOEATION COMBUSTION CHAMBER FOB INTERN AL-COMIBUSTION ENGINES.

Application filed October 11, 1926, Serial No. 140,728. Renewed December 4:, 1923.

My invention relates to a combustion chamber for internal combustion engine cylinders of a form adapted to produce turbulence and to avoid or suppress detonation. The invention, while applicable to engines of various types, is especially applicable to engines with valves at the side of the combustion chan1ber,'and more particularly to fourcycle engines of the L-head type. The language of vertical engines is employed herein for convenience of expression, but this is not to impose limitations, as the engine cylinders.

may be horizontal, or inclined, or arranged in various other ways.

According to my invention the'gases traveling ahead of the piston on the compression stroke encounter a body of metal extending downwardly in and forming part of the upper wall of the combustion chamber and are set into excited circulation by being spread outwardlythereby into a substantially annular space inthe combustion chamber surrounding said downwardly extending body. This downwardly projecting part of the combustion chamber wall is preferably of generally dome-like or frusto-conical shape, with its smaller cud directed down toward the piston. Further it is preferably provided on its tapering sides with convoluted substantially helical lead surfaces producing a substantally helicoidal form, adapted for imparting a swirling rotational movement to the gases as they enter on the intake stroke. and also as they are drivcn upwardly against the convoluted and inclined helical surfaces upon the compression stroke of the piston.

My invention will be best understood from an embodiment thereof shown in the accompanying drawing and described below.

In said drawing, Fig.1 is a central vertical, fragmentary section of an L-head engine cylinder with a head in accordance with the preferred form of my invention, and Fig. 2 is a bottom plan View of the combustion chamber in the cylinder head.

Reference character indicates the piston, here shown as a flat head piston, though it may be of other forms, working in the swept space 12 of theengine cylinder. The cylinder shown is of the L-head type having side inlet and exhaustvalvcs, one of such valves being shown at 14.

The cylinder head 16 is preferably detachable. Tn the combustion chamber 18 a boss or projection 20 extends downwardly over the piston, and the combustion chamber space is reduced thereby when the piston is in up position to substantially the fornrof an annulus 2%, the nose 2(5 of boss 20 being prefer ably extended down substantially close to the piston head when the piston is in its extreme elevated position as shown in Fig. l.

The boss 20 is preferably generally of inverted frusto-conical form, being smallest at the nose 26 and of increasing diameter upwardly from the piston head. The tapering sides of member 20 are preferably formed with a sort of spiral ramp surface 28. The number of convolutions of the inclined ramp surface 28 may-be varied, if desired, three such convolutions or partial convolutions 28, 28 and 28 being shown for illustration. Bc tween the convolutions of the spiral ramp surfaces and connecting the adjacent convolutions thereof is the convoluted riser surface, which is designated generally by the reference numeral 30, and the separate steps or convolutions thereof by 30, 30" and a Ramp surface 28 and riser surface 30 are preferably merged in tilleted or rounded innet and outer angles 34 and 36, so as to avoid undesirably thin or sharp edges or fins, which would favor objectionable local incandescence. The helicoidal boss 20 is preferably water cooled, and the wall 38 thereof is pre terably of about the same thickness as the rest of the cylinder head wall, and a strengthening rib or partial rib 40 may be provided in the water cooling space for reenforcing purposes. The longitudinal axis of the boss 20 is preferably inclined with respect to the axis of piston'ltl, about as shown in Fig. l, and in such case the cylinder head surface bulged downwardly on that side of member 20 toward the spark plug to give an easy lcad surface 46 connecting up with the ramp surface 28 of member 20. With such inclined axis relation the gases driven against the sub stantially hclicoidal and ramped member 20 will be unequally ati'ccted on the two opposite sides. thus promoting turlnilcnce.

The hole 48 for spark plug 50. is preferably located as near as possible to the middle of the combustion chamber, and, while there may be variation in this respect. its prefer-red position is as indicated in the dravv ings. The space above the valves is preforably of smooth uninterrupted open sweep to avoid condensation in this region and to per Init free and uninterrupted flow of the gases.

tically split any such wave, into separate Without commitment to a particular theory,.

not containing anti-detonating components,

with a compression ratio of the order of 6 1 or higher and cvenwithmaterialadvance in ignition timing, is due to combined spreading and swirling turbulence of the gases in the com bustion chamber and to the avoidance of any stagnant recessed or. pocketed portions of gas, that the body of metal 20 extending down within the combustion chamber favors surface combustion and speeding up of the ignition flame by condensation adjacent to these metal surfaces, and that the interposition of such body of metal in the path of any pressure wave which may precede the travel of flame from ignition serves not only to pracparts, but also serves, with the furrowed edges and angles of the ramp and riser surfaces 28, 30, to break up any such pressure wave by contact therewith, and by permittin expansion upon passing by or beyond suc ramp and riser'surfaces of the boss 20. Further that any excessive temperature rise which might be productive of detonation is avoided by the provision of ample area for conducting away heat by the Water jacket, and localized incandescence, which might cause preignition, is prevented by the turbulence ofthe gases above-referred to, the excess heat picked up by the gases, as at any points of incipient incandescence, being rapidly withdrawn by the extra extent of water cooled surfaceof the combustion chamber.

It will be observed that the additional preferably water jacketed surfacearea provided in the combustion chamber in the manner described makes it possible to reduce the volume of the combustion chamber while at the same time its surface area is increased,'thus avoiding a condition which would arise if the compression ratio is increased by merely reducing the general height of the combustion chamber, with a corresponding reduction of surface area.

It will beobserved also that in case of engines with detachable heads, the substitution of a new head constructed in accordance with my invention will be sufficient to change the ordinary low compression engine into a high compression engine with substantial absence of detonation even when run on ordinary liquid fuels, and that the dimensions of member 20fcan be chosen to give substantially any desired compression ratio.

The highest benefits of the present invention are realized when complete combustion and absence of carbon deposits are obtained by the use of my improved system of combustion, involving the supplying to the engine intake above the throttle of exhaust gas and air at temperatures and in proportions and quantities meteredto suit the engine requirements of varying speeds and loads, as set forth, for example, in my copending application Serial No. 757,075, filed Dec. 19,

The subjcctmatter of my invention disclosed in this application and not claimed prising a portion of helicoidal step formation in the combustion chamber thereof, and ignition means in exposed relation to said portion of step formation. I I

2. An internal combustion engine comprising a cylinder having a combustionchamber at the end thereof extending laterally therefrom, a piston in said cylinder, intake and exhaust valves in said laterally extending portion of the combustion chamber; said combustion chamber having a portion of helicoidal step formation therein, and ignitionmeans in exposed relation to said last named portion.

3. An internal combustion engine comprising a portion in the. combustion chamber thereof including horizontally extending surfaces consisting of spiral convolutions increasing in magnitude towards one end thereof, and vertically extending surfaces connecting the same; the entire surface of each of the larger of said convolutions being disposed outwardly beyond the surface of the next succeeding smaller convolution.

41. An internal combustion engine comprising acylinder having a combustion chamber at one end thereof, a piston in said cylinder, intake and exhaust valves in said combustion chamber; said combustion chamber having a portion of helicoidal step formation therein in exposed relation to the fuel charge therein, and ignition means in said combustion chamber facing said helicoidal portion.

5. An internal combustion engine compris ing a portion of substantially step formation in the combustion chamber thereof having transversely extending step surfaces and vertically extending riser surfaces therebetween; and said transverse surfaces consisting of spiral convolutions varying in magnitude from one end of said portion towards the other end thereof.

6. An internal combustion engine comprising a portion of substantially step formation in the combustion chamber thereof tapering towards one end and having horizontally extending surfaces and vertically extending surfaces connecting the same; said horizontally extending surfaces consisting of spiral convolutions increasing'in magnitude from the smaller end of said portion towards the larger end thereof.

'2". in inter combustion engine comprising a tapering portion substantially step formation in the combustion chamber thereof having a substantially fiat central surface at the smaller end thereof, and transverse :step surfaces consistingof spiral eonvolutions the wall of the combustion chamber.

' 9. An internal combustion engine comprisin a cylinder having a combustion chamber at the end thereof extending laterally therefrom, a piston in said cylinder. and intake and exhaust valrcs in said'laterally extending portion of the combustion chan'iber; the ceilin;- of said combustion chamber including a portion of helicoidal step formation.

10. in internal combustion engine com prising a cylinder having a conibustion cham-' be" at the end thereof, a projection of step formationextending from the ceiling thereof. and ignition means disposed in oft-set relation to said projection.

11. in internal combustion engine com prising a projection of step formation cx tendinginto the combustion chamber in spaced relation to the all portion thereof. and ignition means disposed atone side of saidprojeetion and facing the step formation surfaces thereof disposed transversely of the direction of propagation of the infiannnationfrom said ignition means.

12. An internal combustion engine comprisinga projection of step formation extending into the combustion chamber in spaced relation to the walls thereof and tapering from the base thereof towards the outer end thereof, and ignition means disposed at one side of said projection in spaced relation thereto and facing the step formation surfaces thereof disposed transversely of the direction of propagation of the intlanunation from said ignition means.

13' An internal combustion engine comprising a portion of step formation extending into th-e'combustion chamber and forming with the opposing portion thereof a passage decreasing in cross-sectional area from one side thereof towards the center thereof and increasing in cross-sectional area from the center thereof towards the ojniosite s thereof, and ignitionnieans disposed l: ally of aml in spaced relation to said of step formation and facing the ste i tion surfaces thereof disposed transyei of the direction of propagation of the intramination from said ignition means.

it. An internal combustion engine com prising a cylinder having a combustion c hilltbcr at the end thereof extending laterally therefrom. a piston in said cylinder. valves n the laterally extendingportion of said combustion chamber; the ceiling of said combustion chamber having a taper-inn b ss extend in; downwardly into the combura ion chaml cr above the piston and serving to proridc an annular expansion space surri'iundine' said boss: said boss including horizontally temling surfaces and vertically oxtei surface: connecting the same. and a lia. tral surface at the outer end therein; said horizontally extending surfa t, on. inn. of spiral conyolutions increasing in height and magnitude towards the base of said boss. and ignition means disposed in the laterally extending portion of said combustion chamber.

1:). An internal combustion engine hating a sitbstantially hclicoidal boss of step formation extendinggdownwardly in the cou'ibustion chamber abovethe piston.

t0. An internal combustion engine hariue a screw surface, tapering boss extending downwardly in the combustion chamber above the p' ton.

17. In a .ur-cycle L-h ad internal combustion engine. a cylinder, :1 piston working; therein, and a head. for said cylinder baring part of its inner wall in the 't'orn ot a substantially helicoid l body of step 't'ornnition with its longitudinal axis inclined with respect to the piston axis and the snmllcstend of said body terminating adjacent to the surface :'.l' the piston when at the top of the stroke.

is. An internal combustion engine comprisiima cylinder. a piston therein, and a cylinder head having a combustion chamber space therein above the piston in the top center position thereof: said combustion chamber space having" a portion of helicoidal step formation therein.

in testimony whereof. l. name hereto.

ist

have signed my ARLINGTOX MOORE.

ltitl li o 

